Cutting Bundle Size with Rollup’s Tree‑Shaking: A Practical Guide for Library Authors
Learn how Rollup’s tree‑shaking can trim unused code from your library, the pitfalls to avoid, and a step‑by‑step example that shows real bundle size gains.
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Learn how Rollup’s tree‑shaking can trim unused code from your library, the pitfalls to avoid, and a step‑by‑step example that shows real bundle size gains.
Learn how to use Core‑JS 3.x to polyfill only the features you need. This guide shows the difference between <code>pure</code> and <code>stable</code> imports, walks through a Promise polyfill example, and explains how to keep your bundle lean.
Rollup's tree-shaking only removes dead code when packages correctly declare sideEffects in package.json. Learn how to configure it, verify the pruning, and avoid common pitfalls that leave unused functions in your production bundle.
Learn how to diagnose and fix 'Circular dependency' warnings in Rollup.js using the Extraction Pattern and Deferred Execution to prevent runtime undefined imports.
Learn how to leverage Rollup's tree-shaking to eliminate dead code from your bundles. Discover the importance of named exports and the risks of the sideEffects flag.
Tree-shaking is a static-analysis contract, not a minifier toggle. Here is the smallest Rollup design that satisfies it, plus checks and failure modes.
Rollup's manualChunks lets you split stable vendor dependencies from churning app code so browsers keep cached third-party code across deploys. Here's a working config, how to verify it, and when splitting backfires.
Learn how to produce a single, executable JavaScript bundle from a TypeScript codebase using Bun v0.7+, verify the output, and recover from common bundling issues.
When bundling a JavaScript library using Rollup, the effectiveness of dead-code elimination depends heavily on the sideEffects property within the package.json . While Rollup performs static analysis on ES modules to identify unused exports, the presence of global mutations or imported CSS can cause the bundler to retain unnecessary code. The uncertainty ari